How Particulars Naturally Belong to (Natural) Classes

Webs and line graphs belong to the classes of quasi-line graphs and claw-free graphs

Graphs with circular symmetry, called webs, are relevant w.r.t. describing the stable set polytopes of two larger graph classes, quasi-line graphs [8,12] and claw-free graphs [7,8]. Providing a decent linear description of the stable set polytopes of claw-free graphs is a long-standing problem [9]. Ben Rebea conjectured a description for quasi-line graphs, see [12]; Chudnovsky and Seymour [2] v...

The Need to Belong

How and When to Flatten Java Classes?

Improving modularity and reusability are two key objectives in object-oriented programming. These objectives are achieved by applying several key concepts, such as data encapsulation and inheritance. A class in an object-oriented system is the basic unit of design. Assessing the quality of an object-oriented class may require flattening the class and representing it as it really is, including a...

The particulars on parechovirus

HISTORICAL BACKGROUND HPeV are nonenveloped, positive-sense, single-stranded RNA picornoviruses that were first detected in 1956 in children with diarrhea. HPeV-1 and HPeV-2 were originally believed to belong to the genus Enterovirus (EV) and were named echoviruses 22 and 23 (1). In 1999, HPeV were assigned their genus name when genomic sequencing proved that they were not EV. At least 14 other...

How to sample natural populations

Strains from nature have been widely used in experimental and evolutionary studies (reviewed by Perkins and Turner 1988, Turner et al. 2001), most recently for creating phylogenetic trees which provide information on speciation (Dettman et al. 2003). Natural populations have usually been sampled by obtaining conidia from visible colonies on burned vegetation, mostly in tropical or subtropical r...